InputFilter.java revision 2f0f44212fc1e86bd7bd54431bf6a0cd62aa093c
19066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project/* 29066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Copyright (C) 2006 The Android Open Source Project 39066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 49066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Licensed under the Apache License, Version 2.0 (the "License"); 59066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * you may not use this file except in compliance with the License. 69066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * You may obtain a copy of the License at 79066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 89066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * http://www.apache.org/licenses/LICENSE-2.0 99066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 109066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Unless required by applicable law or agreed to in writing, software 119066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * distributed under the License is distributed on an "AS IS" BASIS, 129066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 139066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * See the License for the specific language governing permissions and 149066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * limitations under the License. 159066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 169066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 179066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectpackage android.text; 189066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 199066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project/** 209066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * InputFilters can be attached to {@link Editable}s to constrain the 219066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * changes that can be made to them. 229066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 239066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Projectpublic interface InputFilter 249066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project{ 259066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 269066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * This method is called when the buffer is going to replace the 279066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * range <code>dstart … dend</code> of <code>dest</code> 289066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * with the new text from the range <code>start … end</code> 299066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * of <code>source</code>. Return the CharSequence that you would 309066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * like to have placed there instead, including an empty string 319066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * if appropriate, or <code>null</code> to accept the original 329066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * replacement. Be careful to not to reject 0-length replacements, 339066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * as this is what happens when you delete text. Also beware that 349066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * you should not attempt to make any changes to <code>dest</code> 359066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * from this method; you may only examine it for context. 369066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * 379066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * Note: If <var>source</var> is an instance of {@link Spanned} or 389066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * {@link Spannable}, the span objects in the <var>source</var> should be 399066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * copied into the filtered result (i.e. the non-null return value). 409066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * {@link TextUtils#copySpansFrom} can be used for convenience. 419066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 429066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public CharSequence filter(CharSequence source, int start, int end, 439066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project Spanned dest, int dstart, int dend); 449066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 459066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 469066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * This filter will capitalize all the lower case letters that are added 479066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * through edits. 489066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 499066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public static class AllCaps implements InputFilter { 509066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public CharSequence filter(CharSequence source, int start, int end, 519066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project Spanned dest, int dstart, int dend) { 529066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project for (int i = start; i < end; i++) { 539066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project if (Character.isLowerCase(source.charAt(i))) { 549066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project char[] v = new char[end - start]; 559066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project TextUtils.getChars(source, start, end, v, 0); 569066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project String s = new String(v).toUpperCase(); 579066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 589066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project if (source instanceof Spanned) { 599066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project SpannableString sp = new SpannableString(s); 609066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project TextUtils.copySpansFrom((Spanned) source, 619066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project start, end, null, sp, 0); 629066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return sp; 639066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } else { 649066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return s; 659066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 669066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 679066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 689066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 699066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return null; // keep original 709066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 719066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 729066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 739066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project /** 749066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * This filter will constrain edits not to make the length of the text 759066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project * greater than the specified length. 769066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project */ 779066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public static class LengthFilter implements InputFilter { 789066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public LengthFilter(int max) { 799066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project mMax = max; 809066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 819066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 829066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project public CharSequence filter(CharSequence source, int start, int end, 839066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project Spanned dest, int dstart, int dend) { 849066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project int keep = mMax - (dest.length() - (dend - dstart)); 859066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 869066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project if (keep <= 0) { 879066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return ""; 889066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } else if (keep >= end - start) { 899066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project return null; // keep original 909066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } else { 912f0f44212fc1e86bd7bd54431bf6a0cd62aa093cIshibashi Takako keep += start; 922f0f44212fc1e86bd7bd54431bf6a0cd62aa093cIshibashi Takako if (Character.isHighSurrogate(source.charAt(keep - 1))) { 932f0f44212fc1e86bd7bd54431bf6a0cd62aa093cIshibashi Takako --keep; 942f0f44212fc1e86bd7bd54431bf6a0cd62aa093cIshibashi Takako if (keep == start) { 952f0f44212fc1e86bd7bd54431bf6a0cd62aa093cIshibashi Takako return ""; 962f0f44212fc1e86bd7bd54431bf6a0cd62aa093cIshibashi Takako } 972f0f44212fc1e86bd7bd54431bf6a0cd62aa093cIshibashi Takako } 982f0f44212fc1e86bd7bd54431bf6a0cd62aa093cIshibashi Takako return source.subSequence(start, keep); 999066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1009066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1019066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project 1029066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project private int mMax; 1039066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project } 1049066cfe9886ac131c34d59ed0e2d287b0e3c0087The Android Open Source Project} 105